U.S. patent number 11,283,416 [Application Number 16/537,744] was granted by the patent office on 2022-03-22 for loadline switchable push/pull power amplifier.
This patent grant is currently assigned to SKYWORKS SOLUTIONS, INC.. The grantee listed for this patent is SKYWORKS SOLUTIONS, INC.. Invention is credited to Yuan Cao, Yu-Jui Lin, Bo Pan.
United States Patent |
11,283,416 |
Cao , et al. |
March 22, 2022 |
Loadline switchable push/pull power amplifier
Abstract
Systems and methods are provided herein that include an
amplifier arrangement and a balun arrangement that accommodate two
or more frequency bands using various common components that are
operated and/or coupled in differing ways based upon which
frequency band is in operation.
Inventors: |
Cao; Yuan (Milpitas, CA),
Lin; Yu-Jui (Westlake Village, CA), Pan; Bo (Irvine,
CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
SKYWORKS SOLUTIONS, INC. |
Irvine |
CA |
US |
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Assignee: |
SKYWORKS SOLUTIONS, INC.
(Irvine, CA)
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Family
ID: |
1000006186990 |
Appl.
No.: |
16/537,744 |
Filed: |
August 12, 2019 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20200052660 A1 |
Feb 13, 2020 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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62718141 |
Aug 13, 2018 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H03F
1/565 (20130101); H04B 1/04 (20130101); H03F
3/21 (20130101); H04B 1/0067 (20130101); H03F
2200/451 (20130101); H03F 2200/09 (20130101); H03F
2200/387 (20130101) |
Current International
Class: |
H03F
1/56 (20060101); H04B 1/00 (20060101); H04B
1/04 (20060101); H03F 3/21 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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10-2010-0041536 |
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Apr 2010 |
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KR |
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Other References
International Search Report and Written Opinion from corresponding
International Application No. PCT/US2019/046151 dated Dec. 6, 2019.
cited by applicant.
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Primary Examiner: Nguyen; Patricia T
Attorney, Agent or Firm: Lando & Anastasi, LLP
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. .sctn. 119(e) to
U.S. Provisional Patent Application Ser. No. 62/718,141 titled
LOADLINE SWITCHABLE PUSH/PULL POWER AMPLIFIER, filed Aug. 13, 2018,
which is incorporated by reference herein in its entirety.
Claims
What is claimed is:
1. An amplifier system comprising: at least one common amplifier
stage having an input to receive a radio-frequency signal and to
provide a common amplified radio-frequency signal; a first
amplifier stage having an input to receive the common amplified
radio-frequency signal during a first mode of operation and to
provide a first amplified radio-frequency signal in a first
frequency band; a second amplifier stage having an input to receive
the common amplified radio-frequency signal during a second mode of
operation and to provide a second amplified radio-frequency signal
in a second frequency band; a passive signal coupler including a
balanced primary section and an unbalanced secondary section, the
balanced primary section having at least one first input to receive
the first amplified radio-frequency signal from the first amplifier
stage during the first mode of operation and at least one second
input to receive the second amplified radio-frequency signal from
the second amplifier stage during the second mode of operation.
2. The amplifier system of claim 1 wherein the unbalanced secondary
section of the passive signal coupler includes a common output, and
the passive signal coupler is configured to provide the first
amplified radio-frequency signal to the common output during the
first mode of operation and to provide the second amplified
radio-frequency signal to the common output during the second mode
of operation.
3. The amplifier system of claim 2 wherein the at least one first
input of the balanced primary section of the passive signal coupler
includes a first contact and a second contact to receive the first
amplified radio-frequency signal.
4. The amplifier system of claim 3 wherein the at least one second
input of the balanced primary section of the passive signal coupler
includes a third contact and a fourth contact to receive the second
amplified radio-frequency signal.
5. The amplifier system of claim 1 wherein the at least one first
input of the balanced primary section of the passive signal coupler
presents a first impedance to the first amplifier stage and the at
least one second input of the balanced primary section of the
passive signal coupler presents a second impedance to the second
amplifier stage, the second impedance being different than the
first impedance.
6. The amplifier system of claim 2 wherein the unbalanced secondary
section of the passive signal coupler provides the first and second
amplified radio-frequency signals to the common output as
unbalanced signals.
7. The amplifier system of claim 2 further comprising a first
matching network coupled to the common output.
8. The amplifier system of claim 7 further comprising a switch
having an input and a plurality of outputs, the plurality of
outputs including at least a first output and a second output,
wherein the first matching network is coupled between the common
output and the input of the switch.
9. The amplifier system of claim 8 further comprising a second
matching network coupled to the second output of the switch,
wherein the input of switch is selectively coupled to the first
output of the switch during the first mode of operation, and
wherein the input of the switch is selectively coupled to the
second output of the switch and the second matching network during
the second mode of operation.
10. The amplifier system of claim 1 wherein the first and second
amplifier stages are selectively enabled based on the mode of
operation.
11. An amplifier system comprising: a first amplifier stage to
provide a first balanced signal during a first mode of operation,
the first balanced signal having a first frequency in a first
frequency band; a second amplifier stage to provide a second
balanced signal during a second mode of operation, the second
balanced signal having a second frequency in a second frequency
band; and a passive signal coupler including a balanced primary
section and an unbalanced secondary section, the balanced primary
section having at least one first input to receive the first
balanced signal and at least one second input to receive the second
balanced signal, and the unbalanced secondary section to convert
the first balanced signal to a first unbalanced signal during the
first mode of operation and to convert the second balanced signal
to a second unbalanced signal during the second mode of
operation.
12. The amplifier system of claim 11 wherein the first frequency
band and the second frequency band are non-overlapping.
13. The amplifier system of claim 11 further comprising at least
one common amplifier stage, coupled to the first amplifier stage
and the second amplifier stage, to provide a radio frequency signal
to the first amplifier stage and the second amplifier stage during
the first mode of operation and the second mode of operation.
14. The amplifier system of claim 11 wherein the first input of the
balanced primary section of the passive signal coupler includes a
first contact and a second contact to receive the first balanced
signal and to present a first impedance to the first amplifier
stage.
15. The amplifier system of claim 14 wherein the second input of
the balanced primary section of the passive signal coupler includes
a third contact and a fourth contact to receive the second balanced
signal and to present a second impedance to the second amplifier
stage, the second impedance being different than the first
impedance.
16. The amplifier system of claim 11 wherein the unbalanced
secondary section of the passive signal coupler including a common
output to provide the first unbalanced signal during the first mode
of operation and to provide the second unbalanced signal to the
common output during the second mode of operation.
17. The amplifier system of claim 16 further comprising a first
matching network coupled to the common output.
18. The amplifier system of claim 17 further comprising a switch
having an input and a plurality of outputs, the plurality of
outputs including at least a first output and a second output,
wherein the first matching network is coupled between the common
output and the input of the switch.
19. The amplifier system of claim 18 further comprising a second
matching network coupled to the second output of the switch,
wherein the input of the switch is selectively coupled to the first
output of the switch during the first mode of operation, and
wherein the input of the switch is selectively coupled to the
second output of the switch and the second matching network during
the second mode of operation.
20. The amplifier system of claim 11 wherein the first and second
amplifier stages are selectively enabled based on the mode of
operation.
21. A method for controlling an amplifier system having an input
and an output, the method comprising: receiving a signal at the
input; amplifying the signal in at least one common amplifier stage
to produce an amplified signal; further amplifying, in a first
amplifier stage, the amplified signal during a first mode of
operation to provide a first balanced signal in a first frequency
band to a first input of a balanced primary section of a passive
signal coupler; further amplifying, in a second amplifier stage,
the amplified signal during a second mode of operation to provide a
second balanced signal in a second frequency band to a second input
of the balanced primary section of the passive signal coupler, the
second amplifier stage being different than the first amplifier
stage; and converting, via an unbalanced secondary section of the
passive signal coupler, the first balanced signal to a first
unbalanced signal during the first mode of operation and the second
balanced signal to a second unbalanced signal during the second
mode of operation.
22. The method of claim 21 further comprising adjusting an output
impedance at a common output of the unbalanced secondary section of
the passive signal coupler by a first amount and providing one of
the first and second unbalanced signals from the common output to
at least one switched output of a plurality of switched
outputs.
23. The method of claim 22 further comprising switchably providing
the first unbalanced signal to a first switched output of the
plurality of switched outputs during the first mode of operation
and switchably providing the second unbalanced signal to a second
switched output of the plurality of switched outputs during the
second mode of operation.
24. The method of claim 23 further comprising adjusting the output
impedance of the unbalanced secondary section of the passive signal
coupler at the common output by a second amount by providing an
additional impedance at the second switched output.
25. The method of claim 21 further comprising disabling the second
amplifier stage during the first mode of operation and disabling
the first amplifier stage during the second mode of operation.
Description
BACKGROUND
Evolution in wireless communications has resulted in the demand for
devices capable of supporting multiple frequency bands. Each
frequency band generally has differing coding, modulation,
frequency, channel, and power requirements. Each frequency band may
have varying performance requirements and conventionally may
require varying amplifier, matching network, balanced-to-unbalanced
(BALUN) conversion, and/or antenna characteristics, requiring more
components that take up more space, limiting size reductions of
devices, and increasing costs. Conventional approaches to
consolidating support for multiple bands result in compromised
solutions that may lead to significantly reduced performance in one
or more bands.
SUMMARY
Aspects and embodiments are directed to systems and methods of
accommodating two or more frequency bands using various common
components that are operated and/or coupled in differing ways based
upon which frequency band is in operation.
Still other aspects, embodiments, and advantages of these exemplary
aspects and embodiments are discussed in detail below. Embodiments
disclosed herein may be combined with other embodiments in any
manner consistent with at least one of the principles disclosed
herein, and references to "an embodiment," "some embodiments," "an
alternate embodiment," "various embodiments," "one embodiment" or
the like are not necessarily mutually exclusive and are intended to
indicate that a particular feature, structure, or characteristic
described may be included in at least one embodiment. The
appearances of such terms herein are not necessarily all referring
to the same embodiment.
According to one aspect, an amplifier system is provided and
includes at least one common amplifier stage having an input to
receive a radio-frequency signal and to provide a common amplified
radio-frequency signal, a first amplifier stage having an input to
receive the common amplified radio-frequency signal during a first
mode of operation and to provide a first amplified radio-frequency
signal, a second amplifier stage having an input to receive the
common amplified radio-frequency signal during a second mode of
operation and to provide a second amplified radio-frequency signal,
a signal coupler having at least one first input to receive the
first amplified radio-frequency signal from the first amplifier
stage during the first mode of operation and at least one second
input to receive the second amplified radio-frequency signal from
the second amplifier stage during the second mode of operation.
In various embodiments, the signal coupler is configured to provide
the first amplified radio-frequency signal to a common output of
the signal coupler during the first mode of operation and to
provide the second amplified radio-frequency signal to the common
output during the second mode of operation.
In some embodiments, the first amplified radio-frequency signal is
a balanced signal and the at least one first input of the signal
coupler includes a first contact and a second contact to receive
the first amplified radio-frequency signal. In some embodiments,
the second amplified radio-frequency signal is a balanced signal
and the at least one second input of the signal coupler includes a
third contact and a fourth contact to receive the second amplified
radio-frequency signal. In certain embodiments, the at least one
first input of the signal coupler presents a first impedance to the
first amplifier stage and the at least one second input of the
signal coupler presents a second impedance to the second amplifier
stage, the second impedance being different than the first
impedance.
In various embodiments, the signal coupler provides the first and
second amplified radio-frequency signals to the common output as
unbalanced signals. In some embodiments, the amplifier system
includes a first matching network coupled to the common output.
In various embodiments, the amplifier system includes a switch
having an input and a plurality of outputs, the plurality of
outputs including at least a first output and a second output,
wherein the first matching network is coupled between the common
output and the input of the switch. In some embodiments, the
amplifier system includes a second matching network coupled to the
second output of the switch, wherein the input of switch is
selectively coupled to the first output of the switch during the
first mode of operation, and wherein the input of the switch is
selectively coupled to the second output of the switch and the
second matching network during the second mode of operation.
In certain embodiments, the first and second amplifier stages are
selectively enabled based on the mode of operation.
According to another aspect, an amplifier system is provided and
includes a first amplifier stage to provide a first balanced signal
during a first mode of operation, the first balanced signal having
a first frequency in a first frequency band, a second amplifier
stage to provide a second balanced signal during a second mode of
operation, the second balanced signal having a second frequency in
a second frequency band, and a signal coupler to receive the first
balanced signal and the second balanced signal, to convert the
first balanced signal to a first unbalanced signal during the first
mode of operation, and to convert the second balanced signal to a
second unbalanced signal during the second mode of operation.
In certain embodiments, the first frequency band and the second
frequency band are non-overlapping.
In various embodiments, the amplifier system includes at least one
common amplifier stage, coupled to the first amplifier stage and
the second amplifier stage, to provide a radio frequency signal to
the first amplifier stage and the second amplifier stage during the
first mode of operation and the second mode of operation.
In some embodiments, the signal coupler includes a first input
having a first contact and a second contact to receive the first
balanced signal and to present a first impedance to the first
amplifier stage. In some embodiments, the signal coupler includes a
second input having a third contact and a fourth contact to receive
the second balanced signal and to present a second impedance to the
second amplifier stage, the second impedance being different than
the first impedance. In various embodiments, the signal coupler is
configured to provide the first unbalanced signal to a common
output of the signal coupler during the first mode of operation and
to provide the second unbalanced signal to the common output during
the second mode of operation.
In some embodiments, the amplifier system includes a first matching
network coupled to the common output. In various embodiments, the
amplifier system includes a switch having an input and a plurality
of outputs, the plurality of outputs including at least a first
output and a second output, wherein the first matching network is
coupled between the common output and the input of the switch. In
certain embodiments, the amplifier system includes a second
matching network coupled to the second output of the switch,
wherein the input of the switch is selectively coupled to the first
output of the switch during the first mode of operation, and
wherein the input of the switch is selectively coupled to the
second output of the switch and the second matching network during
the second mode of operation.
In certain embodiments, the first and second amplifier stages are
selectively enabled based on the mode of operation.
According to another aspect, a method for controlling an amplifier
system having an input and an output is provided. The method
includes receiving a signal at the input, amplifying the signal in
at least one common amplifier stage to produce an amplified signal,
further amplifying, in a first amplifier stage, the amplified
signal during a first mode of operation to provide a first balanced
signal to a first input of a signal coupler, further amplifying, in
a second amplifier stage, the amplified signal during a second mode
of operation to provide a second balanced signal to a second input
of the signal coupler, the second amplifier stage being different
than the first amplifier stage, and converting, via the signal
coupler, the first balanced signal to a first unbalanced signal
during the first mode of operation and the second balanced signal
to a second unbalanced signal during the second mode of
operation.
In various embodiments, the method includes adjusting an output
impedance of the signal coupler at a common output by a first
amount and providing one of the first and second unbalanced signals
from the common output to at least one switched output of a
plurality of switched outputs. In some embodiments, the method
includes providing the first unbalanced signal to a first switched
output of the plurality of switched outputs during the first mode
of operation and switchably providing the second unbalanced signal
to a second switched output of the plurality of switched outputs
during the second mode of operation.
In certain embodiments, the method includes adjusting the output
impedance of the signal coupler at the common output by a second
amount by providing an additional impedance at the second switched
output.
In some embodiments, the method includes disabling the second
amplifier stage during the first mode of operation and disabling
the first amplifier stage during the second mode of operation.
BRIEF DESCRIPTION OF THE DRAWINGS
Various aspects of at least one embodiment are discussed below with
reference to the accompanying figures, which are not intended to be
drawn to scale. The figures are included to provide illustration
and a further understanding of the various aspects and embodiments,
and are incorporated in and constitute a part of this
specification, but are not intended as a definition of the limits
of the invention. In the figures, each identical or nearly
identical component that is illustrated in various figures may be
represented by a like numeral. For purposes of clarity, not every
component may be labeled in every figure. In the figures:
FIG. 1 is a schematic diagram of a radio frequency power amplifier
arrangement for wireless transmission;
FIG. 2 is a schematic diagram of an example dual-band radio
frequency power amplifier arrangement for wireless
transmission;
FIG. 3 is a schematic diagram of an example of a dual-mode balun
converter for coupling balanced signal input to unbalanced signal
output;
FIG. 4 is a schematic diagram of another example of a dual-mode
balun converter for coupling balanced signal input to unbalanced
signal output;
FIG. 5 is a schematic diagram of another example of a dual-mode
balun converter for coupling balanced signal input to unbalanced
signal output; and
FIG. 6 is a set of graphs illustrating various simulated
performance characteristics for an example power amplifier and
balun arrangement.
DETAILED DESCRIPTION
Various wireless devices operate in multiple frequency bands to
provide communications capability in accord with various wireless
transmission standards. Differing frequency bands may have
differing power requirements, bandwidth requirements, and the like.
Accordingly, conventional multi-band devices may include multiple
power amplifiers, e.g., a different power amplifier for each
frequency band, as well as accordant balun couplers/converters,
matching networks (e.g., impedance matching networks), and antenna
switching components.
Systems and methods in accord with those described herein provide
an amplifier arrangement and a balun arrangement that accommodate
two or more frequency bands using various common components that
are operated and/or coupled in differing ways based upon which
frequency band is in operation. The systems and methods described
herein may further accommodate a common output matching network.
Accordingly, various amplifier and balun arrangements in accord
with those described herein provide multi-band capability with
fewer components than conventional designs and/or with improved
performance over operational modes of conventional designs.
For example, a dual-band device may support two frequency bands,
each in a differing mode of operation. At least one example of a
dual-band device may include a cellular wireless device, such as a
smart phone, that supports second generation (2G) wireless
standards and also supports fourth generation (4G) long term
evolution (LTE) wireless standards. The 2G wireless standards may
allow, or require, higher output transmission power from the device
than do the 4G LTE wireless standards. Additionally, the 2G band
may accommodate two power levels and the 4G LTE band may
accommodate three power levels. Conventional designs for operation
in each of the 2G and 4G LTE modes require two separate amplifiers,
each on a different die (a 2G die and a 4G die), with separate
balun and matching networks, and accordant switching components to
selectively connect these differing hardware components to one or
more antennas. In other conventional designs, a single power
amplifier may be made to accommodate both frequency bands by
limiting output power or making other design compromises such that
the amplifier exhibits enhanced performance in one of the modes or
frequency bands but is hampered in the other. Again, differing
baluns and matching networks, with accordant switching components,
may be required in such conventional single-amplifier designs.
Systems and methods in accord with those described herein include
an amplifier having some components common to each of multiple
modes of operation (e.g., in differing frequency bands or
conforming to different performance requirements and/or standards)
and some components dedicated to each of the modes, along with a
balun design that allows for enhanced coupling to an unbalanced
output regardless of which of the multiple modes of operation are
active. Further, the amplifier and balun arrangements described
herein may accommodate a single output matching network (for
provision of the unbalanced signal to an antenna and/or an antenna
switch) regardless of which of the multiple modes of operation are
active. In some embodiments, an additional matching section may be
selectively coupled to the output to enhance performance in one or
more of the modes of operation.
It is to be appreciated that embodiments of the methods and
apparatuses discussed herein are not limited in application to the
details of construction and the arrangement of components set forth
in the following description or illustrated in the accompanying
drawings. The methods and apparatuses are capable of implementation
in other embodiments and of being practiced or of being carried out
in various ways. Examples of specific implementations are provided
herein for illustrative purposes only and are not intended to be
limiting. Also, the phraseology and terminology used herein is for
the purpose of description and should not be regarded as limiting.
The use herein of "including," "comprising," "having,"
"containing," "involving," and variations thereof is meant to
encompass the items listed thereafter and equivalents thereof as
well as additional items. References to "or" may be construed as
inclusive so that any terms described using "or" may indicate any
of a single, more than one, and all of the described terms. Any
references to front and back, left and right, top and bottom, upper
and lower, end, side, vertical and horizontal, and the like, are
intended for convenience of description, not to limit the present
systems and methods or their components to any one positional or
spatial orientation.
FIG. 1 illustrates a system 100 that includes an amplifier 110
coupled to a balun 120 that further couples to an output matching
network (OMN) 130 that further couples to and feeds a signal to an
antenna 140. The system 100 is an example of an arrangement to
provide an amplified transmit signal to an antenna, e.g., the
antenna 140. In various embodiments, additional components may be
included, such as an antenna switch that may selectively couple the
antenna 140 to differing components (e.g., a receiver amplifier) or
may selectively couple the amplified transmit signal to other
antennas, for example.
The amplifier 110 may be a multi-stage differential push/pull
amplifier having a differential input 112, one or more initial
stages 114, and an output stage 116. FIG. 1 illustrates both sides,
e.g., differential sides, of the output stage 116, e.g., as
"positive" amplifier 116p and "negative" amplifier 116n. In various
embodiments, any of one or more initial stages 114 will also
include "positive" and "negative" sides despite the lack of their
express illustration in the figures. In various embodiments, the
amplifier 110 may be of differing types and may not be of a
differential design. The output stage 116 also includes one or more
bias supplies 118 that provide bias current to the output stage
116. The balun 120 is a signal coupler that provides conversion and
coupling of the differential balanced output of the amplifier 110
to an unbalanced character. The matching network 130 provides
coupling and impedance matching of the unbalanced amplified
transmit signal to the antenna 140, optionally via an antenna
switch (not shown in FIG. 1).
FIG. 2 illustrates a system 200 similar to the system 100 but
arranged for dual modes of operation, e.g., within differing
frequency bands and/or differing standards for performance
characteristics. The system 200 includes a multi-stage amplifier
210, a multi-input balun 230, and an output matching network 240.
The system 200 may optionally include a switch 250 and an optional
selectable matching section 260, in various embodiments.
The amplifier 210 may include multiple stages, similar to the
amplifier 110 of FIG. 1 above, each of which at least partially
amplify a signal prior to reaching a "final" output stage. The
amplifier 210 also includes a plurality of output stages, one for
each of a plurality of modes of operation. Each output stage may be
associated with a mode of operation, and each mode of operation may
be associated with a frequency band and/or performance standard.
For example, the amplifier 210, as shown, includes two output
stages. A first output stage 216 for operation in, e.g., an LTE
mode, and a second output stage 226 for operation in, e.g., a 2G
mode. The first output stage 216 and the second output stage 226
may each receive an amplified signal from a shared common stage 214
having a differential input 212. Each of the output stages 216, 226
are, in this example, differential amplifier output stages.
Accordingly, each of the first output stage 216 and the second
output stage 226 include a "positive" side and a "negative" side.
For instance, the amplifier portion 216p is the positive side
amplifier for the, e.g., LTE mode, and the amplifier portion 216n
is the negative side. Similarly, the amplifier portions 226p and
226n are the positive and negative sides, respectively, for the,
e.g., 2G mode. Additionally, each of the amplifier portions 216p,
216n, 226p, 226n may have a respective bias supply 218, 228.
In various embodiments, the amplifier 210 may be switched between
multiple modes by enabling or disabling the appropriate output
stage 216, 226 in accord with a desired mode of operation. For
example, the system 200 may be operated in 2G mode by enabling the
2G bias 228 and disabling the LTE bias 218. The system 200 may be
operated in LTE mode by enabling the LTE bias 218 and disabling the
2G bias 228. Any bias for a particular amplifier component may be
selectively enabled or disabled by, e.g., a switching element that
selectively connects a bias supply to a bias input, or selectively
enabling or disabling a bias supply, or other means.
In accord with the above, various stages of the amplifier 210 may
be common to multiple modes of operation. For example, the
amplifier 210 may include multiple stages that process a transmit
signal regardless of which mode the transmit signal belongs to,
e.g., regardless of whether the transmit signal is a 2G signal or
an LTE signal. Additionally, the amplifier 210 may have various
stages that are specific to one or more modes. For example, as
illustrated in FIG. 2, the amplifier 210 may have a first output
stage 216 and a second output stage 226 and each may accommodate a
differing mode of operation as described above. In various
embodiments, a multi-stage amplifier for multi-mode operation, such
as the amplifier 210, may include differing stages that are common
to two or more modes and differing stages that are dedicated to one
or another of various modes. In various embodiments, all components
of the amplifier 210 may be incorporated onto a single die.
Accordingly, the amplifier 210 may be a single die amplifier that
provides enhanced performance for each of two or more modes of
operation, e.g., by selectively enabling or disabling various
components of the amplifier 210. In some embodiments, the amplifier
may support a first mode of operation by disabling a particular
component and may support a second mode of operation by enabling
the particular component, e.g., the amplifier may include a
component that is dedicated to a particular mode of operation while
all other components are common to each of the various modes of
operation. In other words, while the amplifier 210 illustrated in
FIG. 2 includes two output stages 216, 226, each of which is
dedicated to one of two modes of operation, other embodiments may
include one or more components dedicated to a first mode of
operation that are disabled when operating in a second mode of
operation, the second mode of operation not requiring any dedicated
components. Further, as discussed above, various embodiments may
support additional modes of operation by including various
components that may be selectively enabled or disabled in various
combinations to support each of the modes of operation.
The multi-input balun 230 accommodates a plurality of modes of
operation (e.g., frequency bands, performance standards) by
accommodating signal inputs at a plurality of nodes (e.g.,
contacts), as described in greater detail below with respect to
FIG. 3. The balun 230 is a signal coupler that provides conversion
and coupling of the differential balanced outputs of the amplifier
210 to an unbalanced character. In various embodiments, the balun
230 is a passive component that does not require switching or
active configuration control to accommodate operation in one mode
over another. For example, the balun 230 accommodates a first,
e.g., LTE, mode of operation by virtue of receiving the LTE signal
at a first set of nodes 232 (or input contacts), and accommodates a
second, e.g., 2G, mode of operation by virtue of receiving the 2G
signal at a second set of nodes 234 (or input contacts).
Accordingly, coupling and matching characteristics of the balun 230
may be different for signals received on the first set of nodes
versus the second set of nodes, and the balun 230 may thereby be
designed to provide appropriate coupling and matching
characteristics for two (or more) modes of operation (e.g.,
frequency bands or other signal characteristics). The balun 230 may
convert a differential balanced signal received on one of the first
and second sets of nodes to produce a single-ended unbalanced
signal at a common output 236.
In various embodiments, the amplifier 210 may accommodate
additional modes of operation (e.g., more than two) by including
additional output stages. In various embodiments, the balun 230 may
accommodate additional modes of operation (e.g., more than two) by
including additional sets of nodes. In various embodiments, some
sets of nodes of the balun 230 may be designed to provide
acceptable performance for each of two or more modes of operation
and/or some output stages of the amplifier 210 may be designed to
provide acceptable performance for each of two or more modes of
operation. Accordingly, in some embodiments, an amplifier may
provide a differing number of output stages than there are sets of
nodes on a balun, e.g., one set of nodes on a balun may be
connected to multiple output stages of an amplifier in some
embodiments, and one output stage of an amplifier may be connected
to multiple sets of nodes of a balun in some embodiments.
The output matching network 240 may be designed and arranged to
provide a dual-band impedance match to an antenna (not shown) and
may thereby accommodate two (or more) modes of operation without
requiring active selection or switching. In some embodiments,
impedance matching for two (or more) modes of operation may be
enhanced or provided, at least in part, by virtue of the distinct
sets of nodes (e.g., 232, 234) of the balun 230 providing differing
input impedance, e.g., as seen from the amplifier 210. In some
embodiments, further enhancement to an impedance match in one or
more of the modes of operation may be accommodated by including an
additional matching section, such as the matching section 260, that
may be selectively coupled to the output of the matching network
240 (e.g., by the switch 250). Accordingly, in some embodiments,
the system 200 may include the matching section 260 and may
selectively decouple the matching section 260 to operate in a first
mode of operation and may selectively couple the matching section
260 to operate in a second mode of operation. Various embodiments
may include other matching sections for the first mode of operation
and/or various other matching sections for various additional modes
of operation.
FIG. 2 includes some example component values that are not intended
to be limiting. The various component values shown may be suitable
for a particular pair of modes of operation in some embodiments,
but other embodiments may include different values to accommodate
varying system requirements and/or performance characteristics.
FIG. 3 illustrates at least one example of a multi-input balun
230a. The balun 230a includes a primary section 310 and a secondary
section 320. The primary section 310 receives a transmit signal at
one of a first set of inputs 232 or a second set of inputs 234, and
electromagnetically couples the transmit signal to the secondary
section 320 to provide an output signal at an output 236. For
example, the first set of inputs 232, including 232a and 232b, may
be coupled to outputs of the output stage 216 that support the
first, e.g., LTE, mode of operation, and the second set of inputs
234, including 234a and 234b, may be coupled to outputs of the
output stage 226 that support the second, e.g., 2G, mode of
operation.
FIG. 4 illustrates another example of a multi-input balun 230b. The
balun 230b is similar to the balun 230a and includes a primary
section 410 and a secondary section 420. The balun 230b is
configured with secondary inputs at a varying location, as compared
to the balun 230a. The primary section 410 receives a transmit
signal at one of a first set of inputs 232 or a second set of
inputs 234, and electromagnetically couples the transmit signal to
the secondary section 420 to provide an output signal at an output
236. For example, the first set of inputs 232, including 232a and
232b, may be coupled to outputs of the output stage 216 that
support the first, e.g., LTE, mode of operation, and the second set
of inputs 234, including 234a and 234b, may be coupled to outputs
of the output stage 226 that support the second, e.g., 2G, mode of
operation.
FIG. 5 illustrates another example of a multi-input balun 230c. The
balun 230c is similar to the baluns 230a, 230b and includes a
primary section 510 and a secondary section 520. The balun 230c may
be an example suitable for manufacture as a laminate assembly. The
primary section 510 receives a transmit signal at one of a first
set of inputs 232 or a second set of inputs 234, and
electromagnetically couples the transmit signal to the secondary
section 520 to provide an output signal at an output 236, including
236a and 236b. For example, the first set of inputs 232, including
232a and 232b, may be coupled to outputs of the output stage 216
that support the first, e.g., LTE, mode of operation, and the
second set of inputs 234, including 234a and 234b, may be coupled
to outputs of the output stage 226 that support the second, e.g.,
2G, mode of operation.
In various embodiments, the locations of the second set of inputs
234 and the first set of inputs 232 to a dual-mode balun may be
selected or positioned at various points, and may be determined by
various electromagnetic modeling and/or testing to determine
enhanced or suitable arrangements for the various intended modes of
operation, thereby accommodating changing performance requirements
and differing applications. Accordingly, the positioning of the
inputs as shown in the figures is illustrative.
FIG. 6 illustrates a number of simulated performance results for
the system 200 operating in various 2G and 4G modes. The graphs 710
are plots of a power added efficiency (in %) of the amplifier 210
across a range of output power settings. The graphs 720 are plots
of a gain (in dB) of the amplifier 210 across a range of output
power settings. Each set of graphs is coded to indicate the
performance is for a first, 4G LTE, mode of operation (`o`), or a
second, 2G, mode of operation (`*`) that selectively includes the
matching section 260.
Embodiments of amplifier arrangements as described herein can be
implemented in a variety of different modules including, for
example, a stand-alone amplifier module, a coupler module, a
front-end module, a module combining the amplifier arrangement with
an antenna switching network, an impedance matching module, an
antenna tuning module, or the like.
Modules may include a substrate and may include various dies and
may include packaging, such as, for example, an overmold to provide
protection and facilitate easier handling. An overmold may be
formed over substrate and dimensioned to substantially encapsulate
the various dies and components thereon. The module may further
include connectivity from the amplifier arrangement or other
components to the exterior of the packaging to provide signal
interconnections, such as an input port connection, output port
connection, coupled port connection, control input connection, etc.
Certain examples may have multiple connections to accommodate
access to various individual components in the module. The various
connections may be provided in part by wirebonds or solder bumps,
for example, and may include multiple electrical connections where
appropriate.
Embodiments of the amplifier arrangements disclosed herein,
optionally packaged into a module, may be advantageously used in a
variety of electronic devices. Examples of the electronic devices
can include, but are not limited to, consumer electronic products
or components thereof, electronic test equipment, communications
infrastructure (such as a base station, router, transmitter, etc.)
and more. Specific examples of such electronic devices can include,
but are not limited to, a mobile phone such as a smart phone, a
tablet, a telephone, a modem, such as a cable modem or otherwise, a
wireless router or access point, a camera, a digital camera, a
portable memory chip, a vehicular electronics system such as an
automotive electronics system or an avionics electronic system, a
wrist watch, a clock, etc. Further, the electronic devices can
include unfinished products.
General examples of an electronic device may include a circuit
board having numerous modules mounted thereon. The circuit board
may have multiple layers and may include circuit elements and
interconnections in the layers and/or mounted on the surface of the
circuit board. Each of the modules may have a multi-layer substrate
within and upon which there may also be various circuit elements
and interconnections. Additionally, the modules may further include
dies, each of which may have multiple layers and include various
circuit elements and interconnections. An amplifier arrangement in
accord with aspects and embodiments disclosed herein may be
implemented within, among, or across any of the layers of the
various structures, e.g., circuit board, substrates, and dies, as
part of an electronic device, such as a cell phone, tablet, smart
device, router, cable modem, wireless access point, etc.
Having described above several aspects of at least one embodiment,
it is to be appreciated various alterations, modifications, and
improvements will readily occur to those skilled in the art. Such
alterations, modifications, and improvements are intended to be
part of this disclosure and are intended to be within the scope of
the invention. Accordingly, the foregoing description and drawings
are by way of example only.
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